I had a hard time finding that bulb at an auto part store as the bulb that came out of my motorguide was not a simple 12v bulb.

I ended up finding it online and ordered several so I didnt habe to mess with it again. I am not sure it makes a difference but I wrapped the bulb in a rag when installing so I didnt get any oil from my fingers on the bulb.

I have not had any problems since replacing it and that process was very easy.